2011-05-06 12:54:23

by Prem Karat

Subject: [PATCH] fs/9p: Fix invalid mount options/args

fs/9p: Fix invalid mount options/args

Without this fix, if any invalid mount options/args are passed while mouting the 9p fs,
no error (-EINVAL) is returned and default arg value is assigned.

This fix returns -EINVAL when an invalid arguement is found while parsing mount options.

Signed-off-by: Prem Karat <[email protected]>
---
fs/9p/v9fs.c | 43 ++++++++++++++++++++++++++++++++++---------
1 files changed, 34 insertions(+), 9 deletions(-)

diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c
index c82b017..033c23e 100644
--- a/fs/9p/v9fs.c
+++ b/fs/9p/v9fs.c
@@ -78,6 +78,25 @@ static const match_table_t tokens = {
{Opt_err, NULL}
};

+/* Interpret mount options for cache mode */
+static int get_cache_mode(char *s)
+{
+ int version = -EINVAL;
+
+ if (!strcmp(s, "loose")) {
+ version = CACHE_LOOSE;
+ P9_DPRINTK(P9_DEBUG_9P, "Cache mode: loose\n");
+ } else if (!strcmp(s, "fscache")) {
+ version = CACHE_FSCACHE;
+ P9_DPRINTK(P9_DEBUG_9P, "Cache mode: fscache\n");
+ } else if (!strcmp(s, "none")) {
+ version = CACHE_NONE;
+ P9_DPRINTK(P9_DEBUG_9P, "Cache mode: none\n");
+ } else
+ printk(KERN_INFO "9p: Unknown Cache mode %s.\n", s);
+ return version;
+}
+
/**
* v9fs_parse_options - parse mount options into session structure
* @v9ses: existing v9fs session information
@@ -97,7 +116,7 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
/* setup defaults */
v9ses->afid = ~0;
v9ses->debug = 0;
- v9ses->cache = 0;
+ v9ses->cache = CACHE_NONE;
#ifdef CONFIG_9P_FSCACHE
v9ses->cachetag = NULL;
#endif
@@ -171,13 +190,13 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
"problem allocating copy of cache arg\n");
goto free_and_return;
}
+ ret = get_cache_mode(s);
+ if (ret == -EINVAL) {
+ kfree(s);
+ goto free_and_return;
+ }

- if (strcmp(s, "loose") == 0)
- v9ses->cache = CACHE_LOOSE;
- else if (strcmp(s, "fscache") == 0)
- v9ses->cache = CACHE_FSCACHE;
- else
- v9ses->cache = CACHE_NONE;
+ v9ses->cache = ret;
kfree(s);
break;

@@ -200,9 +219,15 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
} else {
v9ses->flags |= V9FS_ACCESS_SINGLE;
v9ses->uid = simple_strtoul(s, &e, 10);
- if (*e != '\0')
- v9ses->uid = ~0;
+ if (*e != '\0') {
+ ret = -EINVAL;
+ printk(KERN_INFO "9p: Unknown access "
+ "argument %s.\n", s);
+ kfree(s);
+ goto free_and_return;
+ }
}
+
kfree(s);
break;

--
1.7.4

--
Cheers,
Prem
Linux Technology Center,
IBM Systems & Technology Labs

2011-05-08 17:51:28

by Venkateswararao Jujjuri

Subject: Re: [V9fs-developer] [PATCH] fs/9p: Fix invalid mount options/args

On 05/06/2011 05:54 AM, Prem Karat wrote:
> fs/9p: Fix invalid mount options/args
>
> Without this fix, if any invalid mount options/args are passed while mouting the 9p fs,
> no error (-EINVAL) is returned and default arg value is assigned.
>
> This fix returns -EINVAL when an invalid arguement is found while parsing mount options.
Prem, Thanks for the patch.
Quick question..any reason why you have a new function for cache, and
in-line here?

Thanks,
JV
> Signed-off-by: Prem Karat<[email protected]>
> ---
> fs/9p/v9fs.c | 43 ++++++++++++++++++++++++++++++++++---------
> 1 files changed, 34 insertions(+), 9 deletions(-)
>
> diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c
> index c82b017..033c23e 100644
> --- a/fs/9p/v9fs.c
> +++ b/fs/9p/v9fs.c
> @@ -78,6 +78,25 @@ static const match_table_t tokens = {
> {Opt_err, NULL}
> };
>
> +/* Interpret mount options for cache mode */
> +static int get_cache_mode(char *s)
> +{
> + int version = -EINVAL;
> +
> + if (!strcmp(s, "loose")) {
> + version = CACHE_LOOSE;
> + P9_DPRINTK(P9_DEBUG_9P, "Cache mode: loose\n");
> + } else if (!strcmp(s, "fscache")) {
> + version = CACHE_FSCACHE;
> + P9_DPRINTK(P9_DEBUG_9P, "Cache mode: fscache\n");
> + } else if (!strcmp(s, "none")) {
> + version = CACHE_NONE;
> + P9_DPRINTK(P9_DEBUG_9P, "Cache mode: none\n");
> + } else
> + printk(KERN_INFO "9p: Unknown Cache mode %s.\n", s);
> + return version;
> +}
> +
> /**
> * v9fs_parse_options - parse mount options into session structure
> * @v9ses: existing v9fs session information
> @@ -97,7 +116,7 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
> /* setup defaults */
> v9ses->afid = ~0;
> v9ses->debug = 0;
> - v9ses->cache = 0;
> + v9ses->cache = CACHE_NONE;
> #ifdef CONFIG_9P_FSCACHE
> v9ses->cachetag = NULL;
> #endif
> @@ -171,13 +190,13 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
> "problem allocating copy of cache arg\n");
> goto free_and_return;
> }
> + ret = get_cache_mode(s);
> + if (ret == -EINVAL) {
> + kfree(s);
> + goto free_and_return;
> + }
>
> - if (strcmp(s, "loose") == 0)
> - v9ses->cache = CACHE_LOOSE;
> - else if (strcmp(s, "fscache") == 0)
> - v9ses->cache = CACHE_FSCACHE;
> - else
> - v9ses->cache = CACHE_NONE;
> + v9ses->cache = ret;
> kfree(s);
> break;
>
> @@ -200,9 +219,15 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
> } else {
> v9ses->flags |= V9FS_ACCESS_SINGLE;
> v9ses->uid = simple_strtoul(s,&e, 10);
> - if (*e != '\0')
> - v9ses->uid = ~0;
> + if (*e != '\0') {
> + ret = -EINVAL;
> + printk(KERN_INFO "9p: Unknown access "
> + "argument %s.\n", s);
> + kfree(s);
> + goto free_and_return;


> + }
> }
> +
> kfree(s);
> break;
>

2011-05-11 15:50:51

by Prem Karat

Subject: Re: [V9fs-developer] [PATCH] fs/9p: Fix invalid mount options/args

Hi JV,

Apologies for the delay in response & Thanks for reviewing it.

On 05/08/11 10:51am, Venkateswararao Jujjuri wrote:
> On 05/06/2011 05:54 AM, Prem Karat wrote:
> >fs/9p: Fix invalid mount options/args
> >
> >Without this fix, if any invalid mount options/args are passed while mouting the 9p fs,
> >no error (-EINVAL) is returned and default arg value is assigned.
> >
> >This fix returns -EINVAL when an invalid arguement is found while parsing mount options.
> Prem, Thanks for the patch.
> Quick question..any reason why you have a new function for cache,
> and in-line here?
No specific reason. Just wanted the code to be in consistent with net/9p/client.c (get_protocol_version()).
>
> Thanks,
> JV
> >Signed-off-by: Prem Karat<[email protected]>
> >---
> > fs/9p/v9fs.c | 43 ++++++++++++++++++++++++++++++++++---------
> > 1 files changed, 34 insertions(+), 9 deletions(-)
> >
> >diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c
> >index c82b017..033c23e 100644
> >--- a/fs/9p/v9fs.c
> >+++ b/fs/9p/v9fs.c
> >@@ -78,6 +78,25 @@ static const match_table_t tokens = {
> > {Opt_err, NULL}
> > };
> >
> >+/* Interpret mount options for cache mode */
> >+static int get_cache_mode(char *s)
> >+{
> >+ int version = -EINVAL;
> >+
> >+ if (!strcmp(s, "loose")) {
> >+ version = CACHE_LOOSE;
> >+ P9_DPRINTK(P9_DEBUG_9P, "Cache mode: loose\n");
> >+ } else if (!strcmp(s, "fscache")) {
> >+ version = CACHE_FSCACHE;
> >+ P9_DPRINTK(P9_DEBUG_9P, "Cache mode: fscache\n");
> >+ } else if (!strcmp(s, "none")) {
> >+ version = CACHE_NONE;
> >+ P9_DPRINTK(P9_DEBUG_9P, "Cache mode: none\n");
> >+ } else
> >+ printk(KERN_INFO "9p: Unknown Cache mode %s.\n", s);
> >+ return version;
> >+}
> >+
> > /**
> > * v9fs_parse_options - parse mount options into session structure
> > * @v9ses: existing v9fs session information
> >@@ -97,7 +116,7 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
> > /* setup defaults */
> > v9ses->afid = ~0;
> > v9ses->debug = 0;
> >- v9ses->cache = 0;
> >+ v9ses->cache = CACHE_NONE;
> > #ifdef CONFIG_9P_FSCACHE
> > v9ses->cachetag = NULL;
> > #endif
> >@@ -171,13 +190,13 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
> > "problem allocating copy of cache arg\n");
> > goto free_and_return;
> > }
> >+ ret = get_cache_mode(s);
> >+ if (ret == -EINVAL) {
> >+ kfree(s);
> >+ goto free_and_return;
> >+ }
> >
> >- if (strcmp(s, "loose") == 0)
> >- v9ses->cache = CACHE_LOOSE;
> >- else if (strcmp(s, "fscache") == 0)
> >- v9ses->cache = CACHE_FSCACHE;
> >- else
> >- v9ses->cache = CACHE_NONE;
> >+ v9ses->cache = ret;
> > kfree(s);
> > break;
> >
> >@@ -200,9 +219,15 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
> > } else {
> > v9ses->flags |= V9FS_ACCESS_SINGLE;
> > v9ses->uid = simple_strtoul(s,&e, 10);
> >- if (*e != '\0')
> >- v9ses->uid = ~0;
> >+ if (*e != '\0') {
> >+ ret = -EINVAL;
> >+ printk(KERN_INFO "9p: Unknown access "
> >+ "argument %s.\n", s);
> >+ kfree(s);
> >+ goto free_and_return;
>
>
> >+ }
> > }
> >+
> > kfree(s);
> > break;
> >
>

--
Cheers,
Prem
Linux Technology Center,
IBM Systems & Technology Labs
DID: 41776362